Party-line-indicating key.



C. G. BRADBURY.

PARTY LINE INDIGATING KEY.

AYPLIOA'HON FILED MAR. 11, 1907.

Patented sept. 22,1908.

2 EHEITBf-SHEET 1.

C. C. BRADBURY.

PARTY LINE INDIGATING KEY.

APPLICATION FILED mnu, 1907.

Patented sept. 22, 190s.

ioA

UNITED STATES PATENT OFFICE.

CLIFFORD O. BRADBURY, OF CHICAGO, ILLINOIS, ASSIGNOR TO'KELLOGG SWITGIIBOARD ANI) SUPPLY COMPANY, OF CHICAGO, ILLINOIS, A CORPORATION OF ILLINOIS.

PARTY-LINE-INDICATING KEY.

Application filed March 11, 1907.

To all whom it may concern.'

Be it known that I, CLIFFORD C. BRAD- BURY, a citizen of the 'United States, residing in Chicago, countyl of Cook, and State of Illinois, have invented certain new and use'lul Improvements in Party -Line Indicating Keys, of which the following is a specication.

My invention relates to party line telephone ringing keys, and has -for its object the provision of a key operating by means of levers, and in which. the positions of the levers themselves will indicate to the operator the last key operated. Such a key is called an indicating ringing key, and its particular utility is to indicate to a telephone operator which ot a plurality oi subscribers on a line has been last called so that il the subscriber does not answer immediately `he may be called again without it being necessary 'lier the operator to inquire the number a second time, or to remember which key was last pressed.

A further object ol my invention is to construct this keyso that it will be impossible to actuate more than one set of springs simultaneously. il

A still 'further object of my invention is to provide a key which shall be simple and inexpensive to manufacture, and which 'shall be durable and ellicient in its practical operation.

My invention is a species oi the generic invention disclosed in Patent No. 720,885, only in that it uses the lever itself as the indicating means, the present invention providing means by which a plurality oil levers may be arranged to cooperate, and thereby indicate the last ol a plurality ol subscribers signaled when there' are more than two subscribers on the same line. rlhe arrangement ol" said. patent is capable oit selectively signaling only two subscribers.

Two speciiic forms of my invention are shown in the accompanying drawings, in which, y

Figure 1 is a section through my key on the line 1-1 oi Fig. 8 Fio. 2 is one ol the cams ol'A Fig. 1 5 Fig. 3 is an. end elevation ot my invention 5 Fig. 4 is an isometric drawing ol the disassembled l over mechanism of Fig. 1 V; Fig. 5 is an isometric drawing el the frame, 'friction springs and escutcheon plate; Fig. 6 shows the connection oil this key with a telephone Specification of Letters Patent.

Patented Sept. 22, 1908.

Serial No. 361,815.

system; Fig. 7 is a section on the line '7 7 ol Fig. 8 of a dillierent 'form oi my invention; Fig. 8 is an end elevation of this second l'orm, Fig. Q is an isometric drawing ol the disassembled lever mechanism of Fig. 7 g and Fig. 10 is an isometric drawing el the trame and. escutcheon plate.

Referring to the term of my invention shown in Figs. 1 to 5, the so-called cams 1 and 2, each being circular in form, are provided with a slot 3, such as might be formed with a thin saw, such slot extending from the inner edge el" each, oi these cams halil way through. These cams are mounted in the T shaped trame 4, which carries at its lower end a plurality elY sets olisprings 5, mounted upon insulating blocks 6 and secured. to the frame by the screws 7. The escutcheon plate 8, which may be et metal or rubber, is secured to the upper face et the trame for the purpose ol presenting a conrely external appearance. Each cam is supplied with a lever Q, which is adapted to be tilted by the telephone operator in the act of ringing or calling a desired subscriber. llivoted to the center ol: each ol the cams 1 and 2 are the straddling members 10, having the cross portions 11 adapted to be engaged by the shoulders 12 when the cams are tilted su'lliciently in either direction. A pair of rollers 13 is secured to the lower end of each of the members 10 by moans of a pivot 14, these rollers normally standing between the long springs of the groups 5 in such manner that when the lever is thrown to its 'lull tilt in either direction the rollers will engage the long springs which bear upon one sido ci the rollers, and thereby deflect the springs to control the circuits through the associated contacts. These contact springs have sullcient resilience to return the rollers to their normal position when the pressure is removed from the lever, but owing to the extra space between the shoulders 12, the cam and lever will not be returned to their normal positions, but will stand in a position intermediate oi the erect and actuating positions, this intermediate position being known as the indicating position.

In order that the actuation oi either lever will restore the lirst er actuated lever 'from its indicating position to its erect position a small sliding plate 15 is placed with its ends extending into the slots 3 ol: each of the cams.

its full extent in either direction, one ofl these pins will engage the plate, and slide it 'firmly against the pins of the other cam, and thereby restore the other cam to its vertical position. Tt will be seen by this that when a lever is tilted inwardly or when one lever is tilted towards the other the pin 16 of the tilted lever becomes actuative and engages the end of the plate, while if a lever is outwardly tilted or tilted away from the other the pin 1T of the tilted lever will become actuative to slide the plate.

In order lthat the cams will not move from the indicating; position to the erect or vertical position too readily the thin springs 1S are placed between the horizontal limbs of the frame, and are adapted to press against the sides of each of the cams with a slight pressure. These springs are provided with the notches 19 which register with the top of the vertical portion of the frame for the purpose of holding the springs in place.

Other means may be employed for furnishing the resistance to the movement of the limbs, one example of which is shown in the second modification of my invention. In this modification similar parts to those described in the iirst modification are indicated by the same characters. The cams of this modification are, however, of slightly differ ent form and carry upon their lower portions the extensions 20, to which are secured the large rubber or insulated spring actuating members 21. The lower part of each of these members is cylindrical in form, while the upper part is extended and slotted so that it will straddle the extension 20 upon the lower part of the cam. This member 21 is provided with the shoulders 22 within the slot, one of these shoulders being adapted to engage the side of the cam when the latter is tilted to the position shown in Fig. 6, which is the indicating position. A further actuation of this lever will press the member 21 against the long spring of the group 5 such as to actuate the contacts in the usual manner. The resilience of this spring will immediately return the lever to the position shown. The long springs on each side of the member 21 are provided with sufficient resilience and normal pressure against the member 21 to oil'er considerable resistance or friction against its movement about its supporting pivot. In this manner the lever 9 is held with considerable firmness in any position in which it may be placed between the limits of its two indicating positions. The indicating feature of this key is the same as that described in connection with the first modification, the small plate 14 being adapted to be longitudinally moved by the actuation of either lever in either direction to restore the other lever to its erect position.

Heretofore multiple contacts upon ringing keys have been objectionable for the reason that the actuation of more than one key connected two or more of the ringing current sources together through the key contacts. These ringing current sources when thus short circuited would often furnish sull icient current to destroy the protect-ive devices of the circuit and thus cause considerable delay and inconvenience. This short circuiting of sources is, however, impossible with my key, because the plate l5 is made of sufficient length that two of the levers may not be moved to a tilt greater than the indicating position simultaneously. It will be seen that if it is attempted to simultaneously tilt the levers toward one another the pins 16 will engage the plate 15 and stop the movement of the levers before any of the springs become actuative. If the levers are tilted away from one another the pins 17 will engage the plate, and if the levcrs are tilted in the same direction the pin 17 of one cani and the pin 16 of the other will engage the plate.

The keys may, of course, as is well known in the art, be supplied with series contacts upon one side, and multiple contacts upon the other side, or may be supplied with any other combination of contacts desired for the particular circuit with which the keys are to be used.

My invention is illustrated and described with respect to two specific modifications, to which, however, T do not wish to be unduly limite'd, it being quite possible to construct other modifications without in any way departing from the s pirit or scope of my inven tion.

Vhat I claim is:

1. In a self-indicating operators key, a plurality of levers, switch springs actuated by the tilting of said levers, and means for causing the levers themselves to indicate the last set of switch springs actuated and released, substantially as described.

2. In a self-indicating operators key, a plurality of cooperating levers, sets of switch springs individually actuated by the individual operation of said levers, and means for causing the lever last operated to itself indicate the last set of springs actuated and released, substantially as described.

3. In a self-indicating operators key, the combination with a plurality of levers, switch springs actuated by the operation of said levers, said levers having a normal position, an actuating position and an intermediate indieating position, and means for restoring one of the levers from its indicating position to its normal position when another lever is tilted to its actuating position, substantially as described.

4. In a self-indicating operators key, a plurality of levers, switch springs actuated by the tilting of such levers, means for indicating by the lever itself the last set of switch springs actuated and released, and .means for removing such indication when another set oi springs is actuated, substantially as described.

5. In a key, the combination with a support, of a pair el" levers mounted in the support and having normal, indicating and actuating positions, switch contacts controlled by the levers, and means to return one lever to its normal position when the other is moved to its actuating` position, substantially as described.

6. In an operators ringing key, the combination with a plurality of levers, each adapted to be tilted in two directions, two sets of switch springs for each lever, one set being adapted to be actuated when its lever is tilted in one direction, and another set being adapted to be actuated when the same lever is tilted in the other direction, each lever having a vertical position, two indicating positions and two actuating positions, means for automatically returning to its indicating position the lever last pressed to its actuating position, and means to return said lever to its normal position when another lever' is pressed to its actuating position, substantially as described.

7. In an operators indicating` key, a pivoted lever having a normal, an indicating and an actuating position, switch springs `for the key adapted to be actuated when the lever is moved to its actuating position, a second lever associated therewith, and .means to restore the ilirst lever to its normal position when the second lever is moved to its actuated position, substantially as described.

S. In an operator-s ringing key, the combination with a plurality of pivoted levers, each lever having a vertical position, a partially tilted or indicating position and a completely tilted or actuating position, means to restore either lever from its indicating position to its vertical position when another lever is thrown to its actuating position, and means to prevent the levers irom too readily moving from the normal to the indicating position, substantially as described.

9. In an operators ringing key, the combination with a plurality of pivoted levers, each having a vertical position, a partially tilted or indicating position, and a further tilted or actuating position, an abutment above and below the pivot of each lever, a movable member extending between the levers and adapted to be pressedl against the upper or lower abutment oi either lever to move the lever to its vertical position, such member being moved by the actuation oi either lever to restore the other lever, substantially as described.

1.0. In an operators ringing key, the combination with a plurality of levers, switch. springs disposed upon each side of said levers, a set of said springs being individually actuated by the deilection of each lever in each direction, each lever having 'live positions, a normal position, and an indicating and an actuating position on each side oiz the normal position, and means for restoring a lever from either of its indicating positions to its normal position by the movement ol another lever to either of its actuating positions, substantially as described.

11. In an operators ringing key, the combination with a plurality of levers, said levers having normal, indicating and operative positions, switch springs controlled by the actuation of said levers, and means operative when one of said lovers is moved to its actuated position for preventing the movement of another ci said levers, substantially as described.

l2. In an operators ringing key, the combination of a support, pivoted cams mounted in the support, contact springs, means for actuating said springs, said means permitting the movement of the cams to an indicating position without actuating the springs, and means to restore one cam to a vertical position when another is moved to its actuating position, substantially as described..

13. In a key, the combination with a support, of cams mounted in the support, a plate mounted in the support and extending into slots in the cams, said plate being moved by the movement of either of the cams to move the other cam, substantially as described.

lli. In an indicating key, a plurality of switches and a plurality of switch actuating levers adapted to indicate by their positions the last switch actuated and released, substantially as described.

Signed by me at Chicago, county of Cook, and State of Illinois, in the presence ci two witnesses.

CLIFFORD C. BRADBURY.

Writnesses EDITH F. Garan, MAnJonrn E. Grunn. 

